Data Files Conventions (Discussion) May 2006

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Data Files Conventions (Discussion)May 2006

• Peter Schroeder
• UC-Berkeley
• peters_at_ssl.berkeley.edu

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Metadata

• Why we are using the ISTP-compliance standard
• http//spdf.gsfc.nasa.gov/sp_use_of_cdf.html
• Constitute minimum acceptable metadata standard
• Global Attributes
• "Project" "ISTPgtInternational " -
  "Solar-Terrestrial Physics" .
• "Source_name" "GEOTAILgtGeomagnetic Tail" .
• "Discipline" "Space PhysicsgtMagnetospheric
  Science" .
• "Data_type" "K0gtKey Parameter" .
• "Descriptor" "EPIgtEnergetic Particles" - " and
  Ion Composition" .
• "Data_version" "1" .
• "Logical_file_id" "GE_K0_EPI_19920908_V01" .
• "PI_name" "D. Williams" .
• "PI_affiliation" "JHU/APL" .
• "TEXT" "reference to journal article, URL
  address" .
• "Instrument_type" "Magnetic Fields (space)" .
• "Mission_group" "Geotail" .
• "Logical_source" "GE_K0_EPI" .
• "Logical_source_description" "Geotail Magnetic
  Field Key Parameters" .

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More on the ISTP Standard

• Variable Attributes
• "SW_P_Den
• "CATDESC" CDF_CHAR "Ion number density (Solar
  Wind " - "Analyzer), scalar"
• "DEPEND_0" CDF_CHAR "Epoch"
• "DICT_KEY" CDF_CHAR "densitygtion_number
• "DISPLAY_TYPE" CDF_CHAR "time_series"
• "FIELDNAM" CDF_CHAR "Ion Number Density
  (CPI/SWA)"
• "FILLVAL" CDF_REAL4 -1.0e31
• "FORMAT" CDF_CHAR "f8.3"
• "LABLAXIS" CDF_CHAR "Ion N"
• "UNITS" CDF_CHAR "/cc"
• "VALIDMIN" CDF_REAL4 0.01
• "VALIDMAX" CDF_REAL4 1000.0
• "VAR_NOTES" CDF_CHAR "Assuming no helium (0.3 -
  several " - "hundred) if the density is less than
  " - "0.3/cc the higher moments (VEL,TEMP) " -
  "shall not be used because of the poor " -
  "counting statistics."
• "VAR_TYPE" CDF_CHAR "data" .

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Metadata Status for STEREO Data Products

• PLASTIC and IMPACT have both committed to
  providing ISTP-compliant CDFs for basic science
  products
• S/WAVES? Will there be higher level products? How
  will metadata be captured?
• SECCHI products? What kinds of metadata make
  sense?

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Mapping to SPASE

• Basis for VHO API
• The SPASE data system is a model for scientific
  data systems. It is based on the latest web-based
  technologies and is designed to be a distributed
  data systems with a heterogenous mix of platforms
  and systems.
• SPASE website http//www.igpp.ucla.edu/spase/
• ACE Example http//www.srl.caltech.edu/ACE/ASC/SO
  AP/ASC_DataCatalog.xml
• Essentially, a dictionary for constructing search
  queries so that everyone is talking the same
  language
• Work ongoing to improve SPASE for particle data

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More on File Conventions

• http//stereo-ssc.nascom.nasa.gov/intranet/softwar
  e_telecon/2005-04-20/telecon_2005_04_20.txt
• Do we want uniform file naming conventions?
• Standard convention doesnt really seem to work
  for IMPACT STA_L01_PLASTIC_20060420_V02.CDF
• Need ability to reflect subproducts for IMPACT
  STB_L1_SWEA_DISB_20061106_V01.cdf